Passenger conveyors, such as escalators and moving walks, typically include a continuous loop of sequentially connected treadplates, a pair of handrails and a pair of balustrades extending along side the treadplates, and a drive system. The treadplates may be steps (escalators) or flat pallets (moving walks). The drive system includes a drive sprocket engaged with a pair of step or pallet chains that are connected to the treadplates. The drive system also provides the motive force for the handrails as they rotate about the balustrades.
The balustrade typically includes a linear section that extends the length of the conveyor and a pair of newels that extend beyond the ends of the conveyor. The newels provide means to extend the handrails into the areas in which the passengers are entering or exiting the conveyor and contribute to the safety of the conveyor. A typical newel is curved to permit the handrail to reverse direction for the return to the opposite end of the conveyor.
The balustrade includes a handrail guide that retains the handrail to the balustrade. The handrail engages in sliding contact with the handrail guide. The newel includes a newel guide for supporting and guiding the handrail around the newel. The tensioned handrail exerts the maximum contact force on the newel because of the reversal in direction. To accommodate the forces associated with the reversal in direction of the tensioned handrail, the newel guide includes a plurality of rollers that define a rolling contact surface for the handrail.
Assembly of the balustrade is a labor intensive process. The conventional newel guide is formed from sheet metal and includes a channel for supporting the rollers, a second channel to engage the balustrade, and a plurality of plastic deflectors. The channels are bonded together by spot welding and then deformed to approximate the shape of the newel. The second channel is then bored to fasten it to the newel, which is typically a glass panel. Finally, the plastic deflectors are fastened to the channels by screws and bonded to the newel. Due to the curved edge of the newel, the assembly of the newel guide to the newel may require extensive rework to get the pieces to fit together properly.
The above art notwithstanding, scientists and engineers under the direction of Applicant's Assignee are working to develop balustrades that are sturdy and that are inexpensive to manufacture and assemble.